Leaf spring pavement joint seal

ABSTRACT

An expansion joint for roadbed slabs. Two parallel and elongated plates are each provided with resilient struck-out tongues. The tongues of one plate engage opposite portions of the other plate, and vice versa. In an embodiment, the tongues press against one another. Another embodiment has a central plate from which the tongues are struck out or to which the tongues are attached. An elastomer sheath partially or completely surrounds the springs and plates to make sealing contact with edges of adjacent modular slabs.

United States Patent [191 Pare 1 July 30, 1974 [54] LEAF SPRING PAVEMENT JOINT SEAL 2,315,588 4/1943 Brickman 404/67 [761 Invent Robert Lee 2? Chiswick 32113333 155%? Silliii:1:33;.......::';;::::::::1::::: 181/23 Edgewood, R1. 02903 [22] Filed: Nov. 9, 1972 Primary Examiner-Nile C. Byers, Jr. [2]] Appl' No: 304,906 Attorney, Agent, or firm-Thomas .1. Greer, Jr.

C [57] ABSTRACT yfcll. An expansion joint for roadbed Slabs. parallel [58] Fieid 49 47 and elongated plates are each provided with resilient 87 3 2 2 struck-out tongues. The tongues of one plate engagev opposite portions of the other plate, and vice versa. In e an embodiment, the tongues press against one an- [56] References Cited other. Another embodiment has a central plate from UNITED A PATENTS which the tongues are struck out or to which the 945.855 l/l9l0 Murray 292/320 7 tongues are attached. An elastomer sheath partially or 1,113,733 10/1914 1 Baker. 404/47 g l tely surrounds the springs and plates to make 1,776,658 9/1930 Galassi 404/67 Sealing Contact with edges of adjacent modular Slabs 1,884.647 10/1932 Gage 404/50 2,071,299 2/1937 Gammeter '404/49 23 Claims, 9 Drawing Figures PATENTEDJULIZOIQH SHEET 3 [IF 3 This invention relatesto an expansion joint displaying particular utility for roadbeds and is of the general type illustrated in my prior U.S. Pat. No. 3,504,597. The invention also displays utility wherever it is desired to form a seal between the edges of spaced panel or modular sections, where the sections are subject to relative motion to thereby vary the spacing between the edges of adjacent panels or sections.

The prior art is aware of an appreciable number of expansion joint constructions for roadbeds. In many, a hollow elastomer element is inserted between two relatively movable panel. members or modular elements, such as spaced slabs-of concrete in a roadbed. Upon ex pansion and contraction of the slabs, as occasioned by variations in ambient temperature, the spacing between them varies and the expansion joint follows this variation for the purpose of maintaining a seal between the two members.

While many prior expansion joints have enjoyed acceptance, nearly all exhibit drawbacks. Thus, with an expansion joint formed completely of elastomer, the problem of plastic set is encountered. This inhibits or precludes complete following of the changes in the gap between the slabs after fairly long time intervals. In other constructions wherein metal springs have been employed problems of spring insertion and'rusting over long time periods. have been encountered, as well as problems of spring manufacture and insertion.

' According to the practice of this invention, an expansion joint is constructed of two generally parallel and elongated. plate elements whose outer faces are parallel to the facing edges of adjacent modular sections. In an embodiment each plate element is provided with integral, struck-out tongues which resiliently contact the opposite facing plate on its flat portions. Ina second embodiment, the struck-out tongues press against one another. lnthis manner, spring force is applied directly against the edge of the gap between the concrete slabs or other modular sections to thereby provide a smooth, stiff face. When receiving the force from the spring tongue elements, the plates transmit forces uniformly to the edges of the gap against which the plates are placed. The plates may be formed of metal such as steel or other fairly stiff, strong, elastic material such as f1- berglass. The plates are easily fabricated, as by punching or, if fiberglass is used, the springs may also be molded or extruded. The composite spring element thus defined by the two parallel and facing plates is either partially or completely encased in an elastomer element or elements which make sealing contact with the facing edges of the modular concrete slabs. The economies resulting from the practice of this invention are derived from the use of an essentially single strip to sertion of the springs into-an encasing, tubular elastoi mer member. Only two main components are required for the practice of the invention, these being a sealing material such as elastomer and spring plates either of metal or of fiberglass or the like.

IN THE DRAWINGS FIG. 1 is a partialperspective view of a plate provided with integral tongues according to the practice of this invention.

FIG. 2 is a view similar to FIG. 1 and illustrates an embodiment.

FIG. 3 is a perspective cross-section of a seal, showing the spring elements encased in atubular, elastomeric sleeve. I

FIG. 4 is a view similar to FIG. 3 and illustrates the spring element of that Figure prior to placement inside the elastomeric sleeve. I

FIG. 5 is a view similar to FIG. 4 and illustratesan embodiment. I

FIG. 6 is a view similar to FIG. 3 and illustrates an embodiment.

FIG. 7 is a view similar to FIG. 4 and illustrates-an embodiment.

FIG. 8 is a view similar to FIG. 7 and illustrates an embodiment.

FIG. 9 is a view similar to FIG. 7 and illustrates an embodiment.

Referring now to FIG. 1 of the drawings, the numeral 10 denotes a plate formed of metal or fiberglass and having apertures 12 defined by the strikingor punching out of tongue portions 14, the latter preferably provided at their ends 16 with a slight inward curve to thereby provide a smooth abutment surfacegThe numeral l7 denotes a flexing slot running from one edge to near an opposite edge. The slots permit limited coplanar flexing of the plate 10. In the embodiment of FIG. 2, a like plate 20 is provided with slots 22 resulting from the striking out of integral tongues 26. The tongues 26 are struck out in such a manner that the remote ends of tongues 28 are curved. It will be noted that slots 22 are of such length to permit limited copla-' nar flexing of. the plate 20. Alternate slots 22 point in opposite directionsln use, two plates such as 10, 10 or 20, 20 are positioned parallel to each otherwith their tongue ends engaging an opposite plate, as will now be described.

FIGS. 3 and.4 illustrate an expansion joint employing the plate spring construction of FIG. 2. Two such plates face, each other, with tongues 26 and curved bearing surfaces 28 in'the indicated position. An elastomer sleeve member 40 surrounds the two spring plates. The elastomer sleeve is similar to the elastomer sleeve 20 shown in my above-noted United States patent. The upper and lower parallel sides may be provided with longitudinal channel elements 42 adapted to seat against the facing edges of the gap between two modular concrete roadbed sections or the like. FIG. 4 illustrates the plates 20 without the elastomer sleeve 40.

The modeof operation will be apparent from a consideration of FIGS. 3 and 4. The springs are slightly compressed when inserted into the gap between the roadbed slabs (one edge of which is shown in phantom lines in FIG. 3) such that when expansion occurs the plates 20 will follow themovement. In the case of contraction of the gap, corresponding; to elongation of the modular roadbed sections, the plates 20 will move towards each other, such motion being resisted by the resilient force of integral tongues 26 having their end curved portions 28 hearing and sliding against flat portionsof the opposite plate.

In FIG. 5 a modification is shown, without illustrating the elastomer sleeve, wherein the curved ends of tongues 26 abut each other instead of the opposite plate. This embodiment permits a wider elastomer joint seal.

In FIG. 6 a central divider plate 50 runs longitudinally of the elastomer sleeve 40, positioned midway thereof, and is provided with separate tongues 52 secured to the plate as by fasteners, i.e., rivets, 54. Separate bearing plates 56 may be employed against which bear curved ends of the tongues. Longitudinally spaced flexing slots 58 permit limiting flexing in a vertical plane. I

FIG. 7 illustrates an embodiment similar to FIG. 6, without showing the elastomeric sleeve. A rigid plate 60 has'secured to opposite sides thereof two curved fiberglass extrusions 62 and 64 whose longitudinal edges are curved, as well as their central portions. Longitudinally spaced slots 70 in plate 60 extend from top and bottom edges towards the central longitudinal region. Fasteners 66 join the three elements at longitudinally spaced locations. Similar slots68 inthe curved, resilient extrusions 62 and 64 permit limited vertical flexing to permit the seal to conform to the roadway contour. Plate 60, aswell as plate 50of FIG. 6, may be fashioned of fiberglass, metal, or rigid plastic. In some applications, the central plate 60 may be omitted and the two curved extrusions 62 and 64 fastened together, as may readily be visualized.

FIG. 8 shows an embodiment, similar to FIG. 7, wherein alternate tongues 72, 76 are spaced along a plate 71 by straight, upstanding fingers 74. The latter correspond to plate 60 of FIG. 7 and plate 50 of FIG. 6. In FIG. 9, resilient tongues 82, 84 are struck from plate 81 in opposite directions.

The mode of operation of the embodiments of FIGS. 5 through 9 is the same as previously described with reference to FIGS. 3 and 4.

I claim:

1. An expansion joint and seal for roadbed slabs and other modular members having a variable width gap between adjacent members, said joint including,

a. a pair of parallel, elongated plates,

b. at'least one of said plates provided with a plurality of resilient tongues extending therefrom, said tongues having portions which abut the opposite plate,

c. an elastomer sheath in contact with and at least partially surrounding said plates and spanning the gap between them, said sheath having portions adapted to abut facing edges of a variable width gap, said sheath portions being urged apart by the action of said resilient tongues.

2. The seal of claim 1 wherein said plate which is provided with said resilient tongues is formed of a stiff, resilient material, and wherein said tongues are integral with said plate.

3. The seal of claim 2 wherein each of said plates is provided with integral tongues, the tongues of one plate abutting the opposite plate.

4. The seal of claim 2 wherein adjacent tongues extend on the same side but in opposite directions from their plate.

5. The seal of claim 2 wherein said tongues of one plate abut corresponding tongues of the other plate.

6. An expansion joint and seal for roadbed slabs and other modular members having a variable width gap between adjacent members, said joint including,

a. a plurality of generally arcuate, resilient tongues,

b. said tongues defining two rows, the tongues of the two rows being spaced from each other, the tongues of the two rows facing in opposite directions, said two tongue rows being fixedly positioned relative to each other, the tongues of the two rows being generally X-shap'ed in cross section,

c. a pair of parallel bearing plates between which said tongues are positioned and against which the ends of said tongues resiliently bear to thereby urge the bearing plates away from each other,

(I. an elastomer sheath at least partially circumferentially surrounding said bearing plates and spanning the gap between them, said sheath having portions adapted to abut facing edges of a variable width 7. The seal of claim 6 wherein said tongues are integral with a plate, with adjacent tongues facing in opposite directions.

8. The seal of claim 7 wherein adjacent tongues are spaced from each other by an upstanding portion of said plate. 1

9. The seal of claim 6 wherein said tongues are secured to a longitudinally extending divider plate, one of said tongue rows being on one side of said divider plate and the other tongue row being on the other side of said divider plate.

10. The seal of claim 9 wherein said divider plate is provided with transversely extending slots running inwardly from the plate edges toward the center of said plate, to thereby permit limited flexing in the plane of the divider plate.

11. An expansion joint and seal for roadbed slabs and other modular members having a variable width gap between adjacent members, said joint including,

a. an elongated divider plate,

b. a pair of elongated, resilient strip elements, arcuate in cross-section, positioned on opposite sides of said divider plate so that the strips thereby define an X-shaped outline in cross-section,

c. a pair of parallel, elongated bearing plates between I which said arcuate, resilient strip elements are positioned and resiliently bear to thereby urge the bearing plates away from each other.

d. an elastomer sheath at least partially circumferentially, surrounding said bearing plates and spanning the gap between them, said sheath having portions adapted to abut facing edges of a variable width gap.

' 12. The joint of claim 11 wherein said resilient strip elements are provided with transverse slots running inwardly from the edges towards the center.

13. An expansion joint and seal for roadbed slabs and other modular members havinga variable width gap between adjacent members, said joint including,

a. a plurality of generally arcuate, resilient tongues,

b. said tongues defining two rows, the tongues of the two rows being spaces from each other, the tongues of the two rows facing in opposite directions, said two tongue rows being fixedly positioned relative to each other, the tongues of the two rows being generally X-shaped in cross section c. an elastomer sheath at least partially circumferentially surround said tongues, with the ends of said tongues abutting said sheath, said sheath having portions adapted to abut facingiedges of a variable width gap.

14. The seal of claim 13 wherein said tongues are in tegral with a plate, with adjacent tongues facing in opposite directions.

15. The seal of claim l4wherein adjacent tongues are spaced from each other by an upstanding portion of said plate. i 16. The seal of claim 13 wherein said tongues are secured to a longitudinally extending divider plate, one of said tongue rows being on one side of said divider plate and the other tongue row being on the other side of said divider plate,

17. The seal of claim 16 wherein said divider plate is provided with transversely extending slots running inwardly from the plate edges toward the center of said plate, to thereby permit limited flexing in the plane of the divider plate. v

18. An expansion joint and seal for roadbed slabs and between adjacent members, and said joint including,

a. an elongated divider plate,

b. a pair of elongated, resilient strip elements, arcw ate in cross-section, positioned on opposite sides of said divider plate so that the strips thereby define an X-shaped outline in cross-section,

c. an elastomer sheath at least partially circumferentially surrounding said resilient strip elements, with the longitudinal edges of said strip-elements abutting said sheath, said sheat having portions adapted to abut facing edges of a variable width gap.

19. The seal of claim 18 wherein said divider plate is provided with transversely extending slots running inwardly from the plate edges toward the center of said in the plane of other modular members having a variable width gap elements are provided with transversely extending slots running inwardly from the edges toward the center.

21. A spring adapted for use in a roadbed joint and seal, including,

a. an elongated, rectangular sheet member of resilient material, b. a plurality of integral tongues extending out from the plane of saidsheet member, adjacent tongues being on one side of said sheet, adjacent tongues having their roots from opposite longitudinal edges of said sheet member, so that adjacent tongues point in opposite directions,

0. said tongues extending generally transversely of b. a plurality of integral tongues extending out from I the plane of said sheet member, adjacent tongues being on one side of said sheet, adjacent tongues having their roots from opposite longitudinal edges of said sheet member, so that adjacent tongues point in opposite directions,

c. said tongues extending generally transversely of said elongated sheet member,

d. said tongues being struck out of said sheet to thereby define a closed slot corresponding to each tongue. l i

23. The spring of claim 22 including,

a. flexing slots extending transversely of said sheet member, each flexing slot running from one edge of said sheet member towards the other edge, said flexing slots being laterally spaced from said slots defined by striking out said'tongues. 

1. An expansion joint and seal for roadbed slabs and other modular members having a variable width gap between adjacent members, said joint including, a. a pair of parallel, elongated plates, b. at least one of said plates provided with a plurality of resilient tongues extending therefrom, said tongues having portions which abut the opposite plate, c. an elastomer sheath in contact with and at least partially surrounding said plates and spanning the gap between them, said sheath having portions adapted to abut facing edges of a variable width gap, said sheath portions being urged apart by the action of said resilient tongues.
 2. The seal of claim 1 wherein said plate which is provided with said resilient tongues is formed of a stiff, resilient material, and wherein said tongues are integral with said plate.
 3. The seal of claim 2 wherein each of said plates is provided with integral tongues, the tongues of one plate abutting the opposite plate.
 4. The seal of claim 2 wherein adjacent tongues extend on the same side but in opposite directions from their plate.
 5. The seal of claim 2 wherein said tongues of one plate abut corresponding tongues of the other plate.
 6. An expansion joint and seal for roadbed slabs and other modular members having a variable width gap between adjacent members, said joint including, a. a plurality of generally arcuate, resilient tongues, b. said tongues defining two rows, the tongues of the two rows being spaced from each other, the tongues of the two rows facing in opposite directions, said two tongue rows being fixedly positioned relative to each other, the tongues of the two rows being generally X-shaped in cross section, c. a pair of parallel bearing plates between which said tongues are positioned and against which the ends of said tongues resiliently bear to thereby urge the bearing plates away from each other, d. an elastomer sheath at least partially circumferentially surrounding said bearing plates and spanning the gap between them, said sheath having portions adapted to abut facing edges of a variable width gap.
 7. The seal of claim 6 wherein said tongues are integral with a plate, with adjacent tongues facing in opposite directions.
 8. The seal of claim 7 wherein adjacent tongues are spaced from each other by an upstanding portion of said plate.
 9. The seal of claim 6 wherein said tongues are secured to a longitudinally eXtending divider plate, one of said tongue rows being on one side of said divider plate and the other tongue row being on the other side of said divider plate.
 10. The seal of claim 9 wherein said divider plate is provided with transversely extending slots running inwardly from the plate edges toward the center of said plate, to thereby permit limited flexing in the plane of the divider plate.
 11. An expansion joint and seal for roadbed slabs and other modular members having a variable width gap between adjacent members, said joint including, a. an elongated divider plate, b. a pair of elongated, resilient strip elements, arcuate in cross-section, positioned on opposite sides of said divider plate so that the strips thereby define an X-shaped outline in cross-section, c. a pair of parallel, elongated bearing plates between which said arcuate, resilient strip elements are positioned and resiliently bear to thereby urge the bearing plates away from each other. d. an elastomer sheath at least partially circumferentially, surrounding said bearing plates and spanning the gap between them, said sheath having portions adapted to abut facing edges of a variable width gap.
 12. The joint of claim 11 wherein said resilient strip elements are provided with transverse slots running inwardly from the edges towards the center.
 13. An expansion joint and seal for roadbed slabs and other modular members having a variable width gap between adjacent members, said joint including, a. a plurality of generally arcuate, resilient tongues, b. said tongues defining two rows, the tongues of the two rows being spaces from each other, the tongues of the two rows facing in opposite directions, said two tongue rows being fixedly positioned relative to each other, the tongues of the two rows being generally X-shaped in cross section c. an elastomer sheath at least partially circumferentially surround said tongues, with the ends of said tongues abutting said sheath, said sheath having portions adapted to abut facing edges of a variable width gap.
 14. The seal of claim 13 wherein said tongues are integral with a plate, with adjacent tongues facing in opposite directions.
 15. The seal of claim 14 wherein adjacent tongues are spaced from each other by an upstanding portion of said plate.
 16. The seal of claim 13 wherein said tongues are secured to a longitudinally extending divider plate, one of said tongue rows being on one side of said divider plate and the other tongue row being on the other side of said divider plate.
 17. The seal of claim 16 wherein said divider plate is provided with transversely extending slots running inwardly from the plate edges toward the center of said plate, to thereby permit limited flexing in the plane of the divider plate.
 18. An expansion joint and seal for roadbed slabs and other modular members having a variable width gap between adjacent members, and said joint including, a. an elongated divider plate, b. a pair of elongated, resilient strip elements, arcuate in cross-section, positioned on opposite sides of said divider plate so that the strips thereby define an X-shaped outline in cross-section, c. an elastomer sheath at least partially circumferentially surrounding said resilient strip elements, with the longitudinal edges of said strip elements abutting said sheath, said sheat having portions adapted to abut facing edges of a variable width gap.
 19. The seal of claim 18 wherein said divider plate is provided with transversely extending slots running inwardly from the plate edges toward the center of said plate, to thereby permit limited flexing in the plane of the divider plate.
 20. The seal of claim 19 wherein said resilient strip elements are provided with transversely extending slots running inwardly from the edges toward the center.
 21. A spring adapted for use in a roadbed joint and seal, including, a. an elongated, rectangular sheet member of resilient material, B. a plurality of integral tongues extending out from the plane of said sheet member, adjacent tongues being on one side of said sheet, adjacent tongues having their roots from opposite longitudinal edges of said sheet member, so that adjacent tongues point in opposite directions, c. said tongues extending generally transversely of said elongated sheet member, d. flexing slots extending transversely of said sheet member, each flexing slot running from one edge of said sheet member towards the other edge.
 22. A spring adapted for use in a roadbed joint and seal, including, a. an elongated, rectangular sheet of resilient material, b. a plurality of integral tongues extending out from the plane of said sheet member, adjacent tongues being on one side of said sheet, adjacent tongues having their roots from opposite longitudinal edges of said sheet member, so that adjacent tongues point in opposite directions, c. said tongues extending generally transversely of said elongated sheet member, d. said tongues being struck out of said sheet to thereby define a closed slot corresponding to each tongue.
 23. The spring of claim 22 including, a. flexing slots extending transversely of said sheet member, each flexing slot running from one edge of said sheet member towards the other edge, said flexing slots being laterally spaced from said slots defined by striking out said tongues. 